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Vector control of a modular multilevel matrix converter operating over the full output-frequency range (2018)
Journal Article
Diaz, M., Cardenas, R., Espinoza, M., Hackl, C. M., Rojas, F., Clare, J. C., & Wheeler, P. (2018). Vector control of a modular multilevel matrix converter operating over the full output-frequency range. IEEE Transactions on Industrial Electronics, doi:10.1109/tie.2018.2870367

The Modular Multilevel Matrix Converter ( M 3 C ) is an ac-to-ac converter topology suitable for the control of high-power variable-speed drives. The control of this converter is complex, particularly when the two ac system frequencies are similar o... Read More

MMC front-end for klystron modulators: an augmented modulation scheme for arm balancing (2018)
Journal Article
Jankovic, M., Costabeber, A., Watson, A. J., Clare, J. C., & Aguglia, D. (2018). MMC front-end for klystron modulators: an augmented modulation scheme for arm balancing. IEEE Transactions on Plasma Science, 46(10), (3325-3333 ). doi:10.1109/TPS.2018.2837619. ISSN 0093-3813

This paper discusses the control of a Modular Multilevel Converter (MMC) used as a grid-interface for the klystron modulators in the Compact Linear Collider (CLIC). The converter has a DC side load which takes short-duration power pulses, causing hig... Read More

An integrated converter and machine control system for MMC-based high power drives (2018)
Journal Article
Espinoza, M., Cardenas, R., Clare, J. C., Soto-Sanchez, D., Diaz, M., Espina, E., & Hackl, C. (in press). An integrated converter and machine control system for MMC-based high power drives. IEEE Transactions on Industrial Electronics, doi:10.1109/TIE.2018.2801839. ISSN 0278-0046

The Modular Multilevel Converter (MMC) is a promising topology for high power drive applications. However, large voltage fluctuations are produced in the floating capacitors when the machine is operating with high stator currents at low rotational sp... Read More

A study on probability of distribution loads based on expectation maximization algorithm (2017)
Conference Proceeding
Ganjavi, A., Christopher, E., Johnson, C. M., & Clare, J. C. (2017). A study on probability of distribution loads based on expectation maximization algorithm. doi:10.1109/ISGT.2017.8086037

In a distribution power network, the load model has no certain pattern or predicted behaviour due to large range of data and changes in energy consumption for end-user consumers. Thus, a powerful analysis based on probabilistic structure is required.... Read More

ESBC: an enhanced modular multilevel converter with H-bridge front end (2017)
Conference Proceeding
Amankwah, E., Costabeber, A., Jasim, O., Trainer, D., & Clare, J. C. (2017). ESBC: an enhanced modular multilevel converter with H-bridge front end

This paper presents the Enhanced Series Bridge Converter (ESBC), a hybrid modular multilevel converter with H-bridge front end suitable for high power grid applications. It retains the advantages of other modular multilevel topologies while offering... Read More

A new analysis for finding the optimum power rating of low voltage distribution power electronics based on statistics and probabilities (2017)
Conference Proceeding
Ganjavi, A., Christopher, E., Johnson, C. M., & Clare, J. C. (2017). A new analysis for finding the optimum power rating of low voltage distribution power electronics based on statistics and probabilities

The continuing trend toward heavier load and high penetration of Distribution Generation (DG) units in low voltage rural distribution feeders requires power electronic-based solution alternatives for voltage regulation purposes. The design of power e... Read More

The Alternate Arm Converter (AAC) - "short-overlap" mode operation - analysis and design parameter selection (2017)
Journal Article
Farr, E., Feldman, R., Clare, J. C., Watson, A. J., & Wheeler, P. (2018). The Alternate Arm Converter (AAC) - "short-overlap" mode operation - analysis and design parameter selection. IEEE Transactions on Power Electronics, 33(7), doi:10.1109/TPEL.2017.2742899. ISSN 0885-8993

This paper presents converter operation principles and theoretical analyses for “short-overlap” mode operation of the Alternate Arm Converter (AAC), which is a type of modular multilevel Voltage Source Converter (VSC) that has been proposed for HVDC... Read More

Control of wind energy conversion systems based on the Modular Multilevel Matrix converter (2017)
Journal Article
Diaz, M., Cardenas, R., Espinoza, M., Mora, A., Rojas, F., Clare, J. C., & Wheeler, P. (2017). Control of wind energy conversion systems based on the Modular Multilevel Matrix converter. IEEE Transactions on Industrial Electronics, 64(11), doi:10.1109/TIE.2017.2733467. ISSN 0278-0046

The nominal power of single Wind Energy Conversion Systems (WECS) has been steadily growing, reaching power ratings close to 10MW. In the power conversion stage, medium-voltage power converters are replacing the conventional low-voltage back-to-back... Read More

Control of a modular multilevel converter with pulsed DC load (2017)
Conference Proceeding
Jankovic, M., Watson, A. J., Costabeber, A., & Clare, J. C. (2017). Control of a modular multilevel converter with pulsed DC load. In 2016 IEEE Energy Conversion Congress and Exposition (ECCE)doi:10.1109/ECCE.2016.7854963

This paper focuses on a Modular Multilevel Converter grid interface for a klystron modulator system that behaves as a pulsed DC load. With such a load, and without mitigating control, the MMC suffers from cell capacitor voltage imbalance between the... Read More

Vector control of an open-ended winding induction machine based on a two-output indirect matrix converter (2017)
Journal Article
Riedemann, J., Clare, J. C., Wheeler, P., Blasco Giménez, R., Cardenas, R., & Pena, R. (in press). Vector control of an open-ended winding induction machine based on a two-output indirect matrix converter. Epe Journal, doi:10.1080/09398368.2016.1261457. ISSN 0939-8368

The open-ended winding induction machine fed from a standard two-level Voltage Source Inverter (VSI) arrangement is an attractive solution for AC drives. An alternative power converter approach is to use an Indirect Matrix Converter (IMC) consisting... Read More

An enhanced dq-based vector control system for modular multilevel converters feeding variable speed drives (2016)
Journal Article
Espinoza, M., Cardenas, R., Diaz, M., & Clare, J. C. (2017). An enhanced dq-based vector control system for modular multilevel converters feeding variable speed drives. IEEE Transactions on Industrial Electronics, 64(4), doi:10.1109/TIE.2016.2637894. ISSN 0278-0046

Modular multilevel converters (M2C) are considered an attractive solution for high power drive applications. However, energy balancing within the converter is complex to achieve, particularly when the machine is operating at low rotational speeds. In... Read More

Submodule power losses balancing algorithms for the modular multilevel converter (2016)
Conference Proceeding
Picas, R., Pou, J., Zaragoza, J., Watson, A. J., Konstantinou, G., Ceballos, S., & Clare, J. C. (2016). Submodule power losses balancing algorithms for the modular multilevel converter

Tolerance and component aging can cause signif¬icant differences in the capacitance values of the submodules (SMs) in a modular multilevel converter (MMC). Depending on the modulation technique, capacitance mismatches may produce uneven switching tra... Read More

The Series Bridge Converter (SBC): design of a compact modular multilevel converter for grid applications (2016)
Conference Proceeding
Amankwah, E. K., Costabeber, A., Watson, A. J., Trainer, D., Jasim, O., Chivite-Zabalza, J., & Clare, J. C. (2016). The Series Bridge Converter (SBC): design of a compact modular multilevel converter for grid applications

This paper presents a novel hybrid modular multilevel voltage source converter suitable for grid applications. The proposed converter retains the advantages of other modular multilevel topologies and can be made more compact making it attractive for... Read More

A simplified space-vector modulation algorithm for four-leg NPC converters (2016)
Journal Article
Rojas, F., Cardenas, R., Kennel, R., Clare, J. C., & Diaz, M. (2016). A simplified space-vector modulation algorithm for four-leg NPC converters. IEEE Transactions on Power Electronics, 32(11), doi:10.1109/TPEL.2016.2618061. ISSN 0885-8993

To interface generation sources and loads to four-wire distribution networks is important to use power converters and modulation methods which provide high performance, flexi¬bility and reliability. To achieve these goals, this paper proposes a simpl... Read More

Experimental comparison of devices thermal cycling in direct matrix converters (DMC) and Indirect Matrix Converters (IMC) using SiC MOSFETs (2016)
Conference Proceeding
Trentin, A., Zanchetta, P., Empringham, L., De Lillo, L., Wheeler, P., & Clare, J. C. (2016). Experimental comparison of devices thermal cycling in direct matrix converters (DMC) and Indirect Matrix Converters (IMC) using SiC MOSFETs

This paper presents an experimental comparison between a Direct Matrix Converter and an Indirect Matrix Converter in terms of semiconductor devices thermal cycling. Both converters have been designed and built using SiC MOSFETs; the Indirect Matrix C... Read More